Bishr ibn al-Muʿtamir

Abū Sahl Bishr ibn al-Muʿtamir ibn Bishr al-Ḥilālī (died 825) was a Muʿtazilite theologian and founder of the Bishriyya school in Baghdad.

The place of Bishr's birth is unknown. Baghdad, Kūfa and Baṣra have all been proposed. Likewise, the date of his birth is unknown, although he was an old man at his death. He studied in Baṣra and later worked as a slave trader in Baghdad. He was an ardent Zaydite missionary, who once promised to convert two people per day, and a staunch advocate of jihad, who financed individual warriors. Caliph Hārūn al-Rashīd (r. 786–809), an opponent of Muʿtazilism, imprisoned Bishr for his alleged Rāfiḍī sympathies. In prison, Bishr wrote 40,000 verses on justice, monotheism and the threat of judgement. They circulated widely and increased his influence, so the caliph released him. In 817, he was a signatory of the decree of the Caliph al-Maʾmūn declaring ʿAlī al-Riḍā his successor.

Ibn al-Nadīm attributes 24 titles to Bishr, mostly polemical works. Another 25 titles are cited by other authors. Many of his theological works were in verse. Only two long poems are preserved in al-Jāḥiẓ's Ḥayawān. The rest are known only from fragments quoted in other Muʿtazilite works, like al-Khayyāṭ's Kitāb al-Intiṣār. He wrote treatises against other Muʿtazilites and attempted refutations of Christianity, Judaism, Kharijism and Zoroastrianism. He wrote, in verse, one of the earliest works intending to prove Muḥammad's prophethood.

Bishr is best known for his concept of the 'engendered act' (tawallud), which refers to the effects engendered or caused by an act of the human will but that are not themselves directly willed. He held humans morally responsible for the effects brought about by their will. He held that the human will was independent of God, which led to accusations of unbelief, although his primary motivation appears to have been to avoid accusing God of evil.